How the H1N1 influenza epidemic spread among university students in Japan: Experience from Shinshu University

Abstract

Background: A worldwide outbreak of influenza A/H1N1 occurred in 2009. Little information is available regarding how the epidemic spread among young people, who comprised the majority of individuals infected with this virus. We therefore assessed the route of transmission of H1N1 among university students at Shinshu University, Japan. Methods: A total of 11,424 students were monitored from August 2009 to March 2010, and those who were diagnosed with confirmed, probable or suspected H1N1 at a hospital or clinic were registered based on self-reporting to the university. Data including date of onset and suspected infection route were collected from the affected patients. Results: Of the 11,424 students, 1016 (8.9%) were infected with H1N1. In most infected students, the suspected transmission route was associated with club activity, followed by close contact with friends and through lectures or laboratory work. Following suspension of activity by clubs with more than 2 infected members, the number of infected individuals decreased. Conclusions: H1N1 influenza spread in the university through specific routes, such as club activity, close contact with friends or lectures or laboratory work. During future outbreaks of influenza, interventions to reduce transmission through these routes may be effective for infection control among university students. Brief ReportThe routes of transmission of H1N1 infection among students were investigated in Shinshu University, Japan. Of the 11,424 students monitored from August 2009 to March 2010March , 1016 were infected with H1N1. The most common route of transmission was club activity, followed by close contact with friends and contacts during lectures or laboratory work. Interventions to reduce transmission through these routes during new outbreaks of influenza may be effective for infection control among university students.

Effect of short-term school closures on the H1N1 pandemic in Japan: a comparative case study

“…At the end of the pandemic, it became clear that H1N1 had spread more among younger people than older people [3][4][5][6][7][8], and there were many infections among schoolchildren [9][10][11]. Measures instituted to prevent the transmission of H1N1 included school closures [12][13][14][15].…”

Evaluation of the spread of pandemic influenza A/H1N1 2009 among Japanese university students

“…This information was thought to be useful for rapid implementation of adequate infection control measures at university organizations [12]. We also reported epidemiological studies among university organizations in Japan [13][14][15][16] and the results indicated that many students were infected with H1N1 and the specific transmission route was identified among university students in Japan. However, in Japan, although the information of H1N1 at educational organizations was distributed broadly it was not featured at universities or colleges in great detail.…”

“…Thus, the proportion of H1N1 influenza patients among university students is probably robust regardless of country. The authors reported that H1N1 was spread through clubs, close friends, apartments, or classrooms during the epidemic period [14]. The transmission routes were investigated by interviews.…”

“…This interview method was used in the first report of the H1N1 pandemic [5] and is, therefore, thought to be appropriate. Transmission routes were investigated based on the interview method and consisted mostly of club activities [14,17,22] or festivals [20,21,27] in Japan. According to the epidemic curve described [14], both the first and second peaks mainly coincided with club activity.…”

Evaluation of factors affecting variations in influenza A/H1N1 history in university students, Japan

“…The designated person at the university interviewed and recorded the characteristics of each student, including name, gender, age, grade and faculty, as well as information on H1N1 infection, including the dates of fever onset and hospital visit, symptoms, the date and route of infection and body temperature. While club activity at the university was suspended several times [18], the school was not closed to university students during this period.…”